Non-$d^0$ Mn-driven ferroelectricity in antiferromagnetic BaMnO${}_3$

James M. Rondinelli, Aaron S. Eidelson, Nicola A. Spaldin

Using first-principles density functional theory we predict a ferroelectric ground state -- driven by off-centering of the magnetic Mn${}^{4+}$ ion -- in perovskite-structure BaMnO$_…